Neuron

Neuron
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Drawing by Santiago Ramón y Cajal of cells in the pigeon cerebellum. (A) Denotes Purkinje cells, an example of a bipolar neuron. (B) Denotes granule cells which are multipolar.
Neurons (also spelled neurones or called nerve cells) are a major class of cells in the nervous system. In vertebrates, they are found in the brain, the spinal cord and in the nerves and ganglia of the peripheral nervous system, and their primary role is to process and transmit neural information. One important characteristic of neurons is that they have excitable membranes which allow them to generate and propagate electrical signals.
The concept of a neuron as the primary computational unit of the nervous system was devised by Spanish anatomist Santiago Ramón y Cajal. Cajal proposed that neurons were discrete cells which communicated with each other via specialized junctions. This became known as the Neuron Doctrine, one of the central tenets of modern neuroscience.
Contents[hide]
1 Anatomy and histology
2 Classes
3 Connectivity
4 Adaptations to carrying action potentials
5 Histology and internal structure
6 Challenges to the neuron doctrine
7 Neurons in the brain
8 See also
9 Sources
10 External links